In general, a roller unit, which is a part having a cylindrical wheel rotatably coupled to a fastening member to reduce frictional resistance by changing sliding friction that is generated in sliding into roller friction, is applied in various fields to various products including furniture or a refrigerator having slidable containing bodies so that a user can smoothly open and close the containing bodies.
A roller unit according to the related art disclosed in Korean Patent No. 10-0822749 includes a wheel (rotary body), a support shaft, and a retainer coupled to a mounting portion of the support shaft to hold the wheel.
However, the roller unit disclosed in Korean Patent No. 10-0822749 necessarily requires a specific retainer for preventing separation of the wheel and the support shaft, so the manufacturing cost is high.
Further, the roller unit has a problem in that the wheel and the support shaft are separated due to corrosion at the portion plastically deformed for coupling the wheel and the support shaft.
There are Korean Patent Nos. 10-0841057 and 10-0654951 as prior art documents relating to such a roller unit.